there are lobsters rarer than blue

app/controllers/application_controller.rb

@@ -70,16 +70,35 @@ class ApplicationController < ActionController::Base
       Rails.logger.info "  Traffic level: #{@traffic.to_i}"
     end
 
-    intensity = (@traffic * 7).floor + 50.0
-    if (blue = (rand(2000000) == 1)) && @user
-      Rails.logger.info "  User #{@user.id} (#{@user.username}) saw blue logo"
-    end
-    color = (blue ? "0000%02x" : "%02x0000")
-    @traffic_color = sprintf(color, intensity > 255 ? 255 : intensity)
+    # logo background intensity is based on traffic
+    intensity = sprintf('%02x', [(@traffic * 7).floor + 50.0, 255].min)
+    set_traffic_style intensity
 
     true
   end
 
+  # http://umaine.edu/lobsterinstitute/files/2011/12/LobsterColorsWeb.pdf
+  def set_traffic_style intensity
+    @traffic_style = "background-color: ##{intensity}0000;"
+    return unless @user
+
+    color = :red
+    [
+      [2_000_000, :blue, "background-color: #0000#{intensity};"],
+      [6, :yellow, "background-color: ##{intensity}#{intensity}00;"],
+      [3, :calico, "background: url(data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAABAAAAAQCAIAAACQkWg2AAAACXBIWXMAAC4jAAAuIwF4pT92AAAABmJLR0QA/wD/AP+gvaeTAAACpElEQVQYGQXBWW8bVRgA0Hu/u814NsdxGsUxztJUzaJSVS1CCCTKE7zxxiP/gH+I+lKKQEVCLUlJ5YTsU8f2eJvxbHfjHLz7sKeU2mhNfvl579vnEPKUEUJxji1YoBaIob4m6+cX8Our/m99TBwmpKGV0hZjz+EO06FHOAKlFNKIcE+p8HYo3rwd/Xk8m+pVEjW4EzIFdjopVVG6Nt1ocpc3ALnIhqMRnF3afz6qd2flcMElAOWu3nm4tr6xMh2cyDpprqwBwdjQ0Uz9fXJ9el0lRTOekVQ13DCKvCXVWO7sdl6+/Gp01cbpv/uHPcqGlUKIr50NZq+Pi7mymrt+GOxvbz9+zKjS5OLi1uV/ZeObAC3un4qgt+c0bL8/v5qJ64WbaocIPC2HzbaDGCOeF0ySJI7vzz9eLuZFpfDq2lZWmd/fx6/e3twkuDIiL3KCysV83D+/xZ/1uhYXjuC6lg0BVk2fHPXcQMWD7L+bvJCettzhEPpgzRIxjbe3u6VMCcXWMEY5E9qisqo1QlRLjDVwxqxSQpBW5CFnSB2PaulyRleCSEtNhDPLltjkdQWYCC+gDVF6pHzU8z8/7IKgVFaVtshSWaQxA2Osz4FiokTQrLRrQCLIXzxr/fT94cFWVFlGmXExNQznnbbzaGcVgb0bJqO8kS5BzmusNAMdYN5mPlsihRh5sL7pRYHXQM+OOj/+8MV3Xx+2mmQ8qQZxkmfKSGXq1Odyt9MShByffKLgcc3JsqrHk3Eyumu6LbkYFHcfsjttSaR5OFP29H755nzw/sq8+yMh/sYKYiRL76dxzOqr9RBsmeisnCWqVlZaMIyxgC5U9eEy7p9awj0ByDiQ7XfgmyfRl0fRwZbb7bLVNmOOXynADDY3Hxzs7+WL5XSY/w/0MGrkMYhXjAAAAABJRU5ErkJggg==) no-repeat center"],
+      [2, :split, "background: linear-gradient(90deg, ##{intensity}0000 50%, #0000#{intensity} 50%)"],
+      [2, :albino, "filter: invert(100%);"],
+    ].each do |cumulative_odds, name, style|
+      break unless rand(cumulative_odds) == 0
+      color = name
+      @traffic_style = style
+    end
+    if color != :red
+      Rails.logger.info "  Lucky user #{@user.username} saw #{color} logo"
+    end
+  end
+
   def require_logged_in_user
     if @user
       true

app/views/layouts/application.html.erb

@@ -44,7 +44,7 @@
   <div id="wrapper">
     <div id="header">
       <div id="headerleft">
-        <a id="l_holder" style="background-color: #<%= @traffic_color %>;"
+        <a id="l_holder" style="<%= @traffic_style %>"
           href="/" title="<%= Rails.application.name %> (Current traffic: <%=
           @traffic.to_i %>)"></a>